Eyelet



ZES

Patented Och 16, 1934 Lasarte iiyama Sylvester it, Giochini, Quincy, Mass., assigner to United Shoe lidaelninery Enumeration, haterson, N. il., a corporation of idea' Jersey Application January if, 31.932, No, 535,335

invention relates to eyelets and to certain problems encountered in setting them in hard materials as distinguished from materials that would be stretched by inserting tight-fitting eyelets therein or by expanding eyelets in procu ess of being inserted therein. The expression hard materials as used herein contemplates metals such as iron, steel, bronze and brass, and the harder kinds of electrical insulating substances such as hard rubbei", balrellte, and compressed nbre. The expression is not intended to include readily stretchable materials such as leather, textile fabrics or those grades of rubber or rubber compounds that have the property of stretching. Nevertheless, it will be apparent that eyelets of the type herein illustrated and described may be useful also in many readily stretchable materials, although they have special advantages and special utility with respect to certain problems encountered in materials that will not be stretched by them.

In certain electrical work, for example radio apparatus and distributors in ignition apparatus for internal combustion engines, satisfactory operation requires permanently tight connections between parts made separately but intended to be rigidly related when assembled. To cite a specific example in which eyelets of the typev contemplated by the present invention and herein illustrated have solved such a problem after eyelets having circular barrels have been tried and have failed to do so, the angularly adjustably support for the make-and-break contact points of the primary circuit interruptor in one well-known distributor for internal combustion engines comprises a plate of hard insulating material mounted on a plate of metal and axed to the latter plate by a plurality of fasteners that extend through both plates. The contact points of the interruptor are mounted respectively on these plates. Consequently to insure positive control of the air-gap when the contact points are separated, it is necessary to eliminate relative edgewise movement of the two plates thus connected.

To avoid failure of the fasteners to enter the holes in the articles of Work, particularly when insertion of the fasteners is to be performed by machinery, the leading ends of the fasteners must be smaller than the holes provided for the fasteners. Even if the fasteners taper toward their leading ends they require expanding to fill the holes after the leading ends have entered. When it was attempted to secure the plates with eyelets having circular barrels suitably tapered to (Git 35m-lati) insure insertion, the barrels dici not fill the holes,l

notwithstanding the fact that tapered maridrels 'were used to expand them in the holes. @n the other hand, when eyelets having circular tapered barrels slightly larger at their larger ends than the holes `were used, the larger ends of the barrels did not enter the holes but were merely crushed axially without sufficient protrusion of their smaller ends to provide for clenching.

The conditions encountered in the use oi rivets are equally adverse, if 'not more so in some respects. For example, gang riveting is hopelessly beyond the range of possibilities whenclose spacing of the rivets is necessary or Where small dimensional discrepancies are of moment. Even when rivets are inserted one at a time by machines they must be smaller than the holes, and relatively heavy riveting pressures are necessary to clench them so tightly as to prevent edgewise` creeping ofthe connected parts.

With these conditions in view, an object of the present invention is to provide an improved type of eyelet that may be inserted in hard materials i by an automatic machine and that will not be collapsed or crushed axially if it fits tightly the wall of the eyelet-receiving hole, and that may be rendered permanently tight if its barrel is initially not quite large enough to fill the hole.

To this end the invention provides an eyelet of ductile metal the barrel of which is provided with a flange at one end, a circular portion at the other end, and one or more longitudinally extending corrugations. As herein illustrated, the unfianged end is tapered to facilitate insertion of the barrel into an eyelet-receiving hole.

The corrugations serve several purposes. For example, lf the corrugated portion is initially so large as to fit tightly in the eyelet-receiving hole, the corrugatlcns not only stiften the barrel against stresses that tend to crush it axially, but they also provide for slight radial contraction if that be necessary to insert the barrel. On the other, hand, if the corrugated portion of the barrel is initially not quite large enough to ll the hole, it may be readily dilated to illl the hole and rendered permanently tight therein by deforming the corrugations during or after insertion.

It is preferable, with regard to stripping the eyelet from the corrugated eyelet-forming punch and die,to impart a slight taper to the corrugated portion of the barrel, but the degree of taper here may be very slight compared with that at the unflanged end of the barrel.

In practice, permanent tightness of an eyelet having the above-described characteristics, in

sion'but Athereafter puts the corrugatlons into a4 hard substances such as metal and other nonelastic materials, may be readily brought about by forcing a tapered tool of circular cross-section into the barrel far enough to compress and deform the corrugations. If the barrel is initially slightly smaller than the hole occupied thereby, the radial force applied by the tapered tool will dilate the barrel until dilation of the outer cor- Irugations is arrested by the wall of the hole. Further movement of the tapered tool into the barrel wil? put'both the inner corrugations and the outer corrugations under compression, since no further dilation of the outer corrugations is possible. Under these conditions` some of the ,metal of the inner corrugations will be forced to iow into the outer corrugations, thus increasing the circumferential magnitude of the latter. Then, when the dilating force is removed, the barrel will not contract but will remain perma- .nently tight in relation to the wall oi the hole.

rlhis permanence of tightness appears to be due to the fact that the final ilowing of the metal or the barrel is produced by compression. -Whether that is the correct'explanation or not, "lue fact remains that the corrugations provide surplus metal and. spaces into which it can flow under compression. The logical explanation, lic d on apparent conditions and proven results, that when the outer diameter of the barrel it heilig increased by the diluting force the metaly .oi the barrel undergoes a slight stretching which puts'it in a state of tension, but when dilation ci? the outer corrugations is arrested by the Wall of the hole further dilation ofthe inner corrugations not only eliminates the state of tenstate of compression.

Thus, when two or more layers or plates of hard material are connected by corrugated eyelets that have been dilated and compressed between hard annular surfaces, theyare positively maintained against relative edgewise creeping. lThis is so irrespective of the pressure with which the layers are maintained one against another clenching the eyelets, since'the dilation and t' compression referred to take eifect on the s ol' the eyelet-receiving holes rather than ou the outer surfaces of the connected layers. Moreover, since the individual corrugatlons oi an eyelet are capable of unequaly and dissimilar, detormatiom an eyelet having such characteristics will counteract discrepancies of small magnitude in the shapes and sizes of the eyelet-receiving holes and slight errors of register of the holes in superposedv layers or platesv of sheet material.

While the above-described eiectsare being produced the smaller endo! the barrel may be clenched. As herein illustrated, the tapered tool for'dilating and compressing the corrugations is the smaller end of the barrel and producing a rollclench.

The initial-emmene' of me .amener end of the eyelet-barrel not only-facilitates vii'isertion `of the eyelet but also facilitates the upsetting and clenchlng of that end, particularly when, as herein shown, it is clenched in circular form. Moreover, the initial circularity at the end mentloned avoids splitting that end into segments when forming a roll-clench therewith.

Referring to the accompanying drawing,

Fig. 1 is a longitudinal section of an eyelet embodying the present invention, the plane of the section being indicated byline I-'I of Fig. 2;

Fig. 3 is a longitudinal section of the eyelet l in the plane indicated by line III- III of Fig. 2 but includes 4broken lines to illustrate the result of dilating the barrel and imparting a roll-clench to the smaller end thereof Fig. 4 is a cross-section of the barrel in its initial condition (see line IV-lV of Fig. 3) and occupying a circular hole in an article of work;

Fig. 5 is a view similar to Fig. 4 except that the barrel has been dilated to fill the hole and the corrugations thereof have been compressed and deformed suillciently to maintain the ultimate degree oi' dilation;

Figs. 8 Aand 'I are sectional views corresponding to Figs. 1 and 3, respectively, except that they illustrate an eyelet asclenched and dilated in an article of work comprising two superposed layers or plateale! hard sheet material;

Fig. 8 is a longitudinal sectional view including co-operatlve eyelet-setting tools, an eyelet as shown in Fig. 1 on the upper tool, and two layers or plates of hard materials lyingon the lower tool in position to receive the eyelet; and

Fig. 9 is a view similar to Fig. 3 except that the -corrugations shown best in Fig. 4. The com gated form is developed in the manufacture of the eyelet by making the eersel initially circular in cross-section throughout its entire length. and thereafter indenting a circular series of internal arcuate corrugations 13, six in the illustrated example, thereby producing also a corresponding circular series of external arcuate corrugations 14. Toward the smaller end 12 of the barrel, the internal corrugations 13 and the external corrugations 14 merge gradually one into another, the originalcircularity of the smaller end i2 being thus preserved (see Fig. `2) This leaves the metal at'the end 12 softer and more ductile than the metal'in the crrugations. Both the internal corlll rugatlons 18 and the external corrugetinns 14 of being drawn Vfrom the center of the area bounded by the rim. oi the flange.

For certain uses in which considerable strength is required, it is preferable to make the eyelets of brass having only s. moderate degree of ductility.

Consequently, as a result of indenting thecorrugations 13, the barrel undergoes a hardening process between the circular portion l1 and the circular end 12 but little or no hardening at the latter. Thercfore, since the end 12 remains relatively soft and ducvtile after the cozrugations have been formed, it is the better adapted to be upsct and clenched without being split into segments. lMoreovexgrsince the corrugations do not extend to theendy 12, the latter may be kupset and clenched'in circular form without undergoing any change in cross-sectional shape.

- Setting tools 0I the type illustrated-1n Figs. 8

Vin

the other. Here also, the individuality of the corrugaticns with respect to dilationv and distortion will counteract the non-alinement of the walls oit the holes sulilciently to prevent all relative creeping of the connected plates. l

As illustrated inl Figs. 8 and 9, the clenchlng tool is provided with an acute circular edge 34 at the intersection of the upsetting suri'ace 22 and a iirusto-conicalouter surface 35. lnv practice, the acute edge 34, when brought to bear against certain materials not too hard or brittle,

for example, compressed ilbre used for electrical'4 insulation, willindent suchmaterials and form annular grooves or depressions into which the clenched ends of the eyelet barrels will be embedded as illustrated in Figs. 6 and '1. One advantage oi such a groove is that it reduces the magnitude of protrusion ci a roll-clenchk from the surface of the work in which the groove is formed. Another is that it avoidsilattening a roll-clench. Again, ii.' burrs are formed on theV clenched end o1' an eyelet they will be buried in the groove.

Having thus described 'my invention, what I claim as new and desire to secure by Letters Patent oi the United States is:

` is provided with a flange at one end, a circular lili dll

tapering portion at the other end,4 an a circular series o! work-engaging corrugation that converge toward said circular tapering portion.

3. An eyelet of ductile metal the barrel of which has ends of different diameters, is circular at its lsmaller end and is provided with a ilange at its other endrand with a circular series of workengaging corrugations that converge toward and merge gradually into circularity at said smaller end.

4. An eyelet of ductile metal the barrel of which 4 provided with a flange at one end, a tapering portion at the other end, and a circular series cf work-engaging corrugations that converge and merge gradually into said tapering portion, the smaller end of said tapering portion being circular.

5. An eyeletof ductile metal the-barrel of which is circular at both ends and provided with a ange at one end and with one or more longitudinally 'extending corrugationa` between its ends.

(i. An eyelet of ductile metal the lbarrel oi which Y '1. An eye1et of ductile mem the barrel of which has circular ends of different diameters, a fiange at the larger end, and one or more corrugations extending lengthwise between its ends.

8. An eyelet of ductile metal the barrel of which 4 has circular ends of different diameters and one or more corrugations extending lengthwise between its ends, the larger end being provided with a ilange and the smaller end being tapered.

9. An eyelet olductile metal the barrel of which has circular ends, a flange -at one end, and one or more indented portions between its ends forming longitudinally extending corrugations.

l0. An eyelet oi.' ductile metal having a barrel, a iiange at one end thereof, the other end being tapered and circular, and a circular series of in dented portions forming longitudinally extending ccrrugations that merge gradually into the intervening external ccrrugations adjacent to said other end.

1l. An eyelet of ductile metal having a barrel, a flange at one end thereof, the other end of the barrel being circular and smaller than the hanged end, and one or more longitudinally extendingl corrugations that merge into circularity near said smaller end.

12. An eyelet of ductile metal the barrel of which tapers from end to end and has a greater degree of taperat its smaller end than elsewhere,

said smaller end being'circular, the larger end having a ilange, and the barrel having one or more corrugatlons extending lengthwise thereof.

13. An eyelet of ductile metal the barrel of which has circular ends of different diameters, a circular series of indented corrugations extending lengthwise thereof nearly but not quite to each end, work-engaging corrugations alternating ing with said indented ccrrugations and converg- .ing toward the smaller end, and a flange at the larger end.

SYLVESTER L. GOOKIN. 

